Question

What is the mole fraction of sulfuric acid in a solution made by adding 34 g of sulfuric acid (H2SO4 = 98 g/mol) to 100 g of water (H2O = 18 g/mol)?

Answer 1

Mole Fraction = 0.059

Step-by-step explanation:

To find the mole fraction, you need to (1) convert grams H₂SO₄ and H₂O to moles (via molar mass) and then (2) calculate the mole fraction.

(Step 1)

Molar Mass (H₂SO₄): 98 g/mol

34 grams H₂SO₄ 1 mole
-------------------------- x ------------------- = 0.347 moles H₂SO₄
98 grams

Molar Mass (H₂O): 18 g/mol

100 grams H₂O 1 mole
------------------------- x -------------------- = 5.56 moles H₂O
18 grams

(Step 2)

moles solute
Mole Fraction = -------------------------------------------------
moles solute + moles solvent

0.347 moles H₂SO₄
Mole Fraction = -----------------------------------------------------------
0.347 moles H₂SO₄ + 5.56 moles H₂O

Mole Fraction = 0.059